L- theanine might be the closest thing we’ve got so far to meditation in a capsule. The traditional therapeutic use of green tea dates back to China 4,700 years ago, and the Japanese regard tea so highly they’ve created a ceremony for it and a separate teahouse in which to serve it. Today, drinking tea still symbolizes psychological calm and contentment for most, and now science is starting to explain the physiological reasons and mechanisms behind these effects. Several scientific publications, including clinical and epidemiological studies, have backed up the health benefits of both black and green teas, with particular focus on L-theanine—a calming amino acid bioactive found to promote alpha-wave brain production (an index of wakeful relaxation similar to that experienced during and directly after meditation).* Here’s all you need to know about nature’s powerful relaxant. Alpha brain-wave production also happens during deep meditation, when sensory inputs are minimized and the mind is generally clear of unwanted thoughts or distractions. Interestingly, stimulating alpha waves has also been shown to boost creativity2 and lift mood. Translation? L-theanine’s effect on brain activity in the alpha band helps you enter the ideal mental state for, well, most things.* In a 2014 Psychopharmacology study, green tea consumption appeared to support performance of working memory by increasing connectivity between frontal and parietal brain regions during working memory processing4.* This is likely because L-theanine has a similar chemical structure to glutamate, which is a neurotransmitter related to memory. L-theanine has also been shown to have a similar boosting effect on dopamine and serotonin levels in the brain in preclinical neurochemistry studies, so more clinical research is warranted.* Additionally, thanks to L-theanine’s impact on GABA synthesis, the “calm down” signal likely plays a part in these sleep health benefits.* The L-theanine content of tea varies considerably, with estimates around 1 to 2% of the dry weight of leaves and a single cup of tea containing around 25 to 60 milligrams 9of L-theanine. Data indicates that L-theanine at “realistic dietary levels” as low as 50 milligrams has significant mental effects10 (on alertness and cognitive arousal).* L-theanine is a premium and effective ingredient found in some high-quality nootropic supplements as well, which help promote cognitive function and brain activity in a convenient, targeted delivery format.* A 2012 study published in The Journal of Nutrition found that L-theanine uptake and metabolism in healthy participants is effective and comparable when provided via capsules or green tea11, so you can leverage the power of this amino acid bioactive in multiple ways! 12 Some ideas to get L-theanine on the regular: As always, consult your doctor or integrative or functional medicine practitioner before you begin taking a supplement or make any changes to your existing supplement routine (especially those with blood pressure considerations, as L-theanine can reduce blood pressure). Together, you can go over any possible interactions and find the form and dose that’s best for you, depending on your unique health profile. When considering a supplement, try to find out as much as you can about the ingredient science, quality, and sourcing as well as bioavailability. Not sure where to start? mindbodygreen’s focus+ offers premium sourcing and quality of energy-promoting ingredients at their full-potency, clinically researched doses—including 100 milligrams of L-theanine (as Suntheanine®), instant- and sustained-release caffeine from antioxidant-rich botanicals (i.e., whole coffee fruit and green coffee beans), Panax ginseng, guarana seed extract, and vitamin B12.* To inform current clinical research, early preclinical dose-response studies in animals were useful to establish safety limits for intake. In animal research (rodents), L-theanine has been demonstrated to be safe even at very high doses (4,000 milligrams per kilogram of body weight per day was the highest dose tested13). Nonetheless, it’s always a good idea to talk to your health care provider first because everyone’s response to foods and supplements are different and depend on individualized factors.
